Gun barrel system

ABSTRACT

A gun barrel system comprises a barrel forward section, a barrel aft section, collar means retaining said forward and aft sections together, a liner disposed within said aft sections, means longitudinally capturing said liner between said forward and aft sections, means rotationally aligning said liner with said forward section, and means for facilitating ready and nondestructive removal of said liner from said aft section.

United States Patent [1 1 Arnold et a1.

[ July 31, 1973 1 GUN BARREL SYSTEM [75] Inventors: William C. Arnold,Milton; Joseph K. Lendway, Burlington; Brian W. Woodman, Burlington;Michael T. McGeellan, Burlington; David P. Perrin, Hinesburg, all of Vt.

[73] Assignee: General Electric Company,

Burlington, Vt.

[221 Filed: Aug. 23, 1971 [2]] Appl. No.: 173,845

[52] US. Cl. 89/16, 42/76 [51] F4" 17/08 [58] Field of Search 89/14, 16;42/76,

[56] References Cited UNITED STATES PATENTS 3,442,172 5/1969 Wehrmann89/16 2,775,164 12/1956 Tillander 89/16 475,071 5/1892 Willson 89/16186,308 1/1877 Crispin 89/16 2,112,144 3/1938 Coupland... 89/163,550,502 12/1970 Keith 89/16 727,767 5/1903 Emery 89/16 PrimaryExaminer-Benjamin A. Borchelt Assistant Examiner-H. J. TudorAtt0rneyBailin L. Kuch et al.

[ ABSTRACT A gun barrel system comprises a barrel forward section, abarrel aft section, collar means retaining said forward and aft sectionstogether, a liner disposed within said aft sections, meanslongitudinally capturing said liner between said forward and aftsections, means rotationally aligning said liner with said forwardsection, and means for facilitating ready and nondestructive removal ofsaid liner from said aft section.

7 Claims, 2 Drawing Figures GUN BARREL SYSTEM BACKGROUND OF THEINVENTION 1. Field of Use This invention relates to a readily replacableliner for a gun barrel, and is especially adapted to a revolving batterygun firing caseless ammunition.

2. Prior Art Liners for gun barrels are well known. Full length liners,for example, are shown in U.S. Pat. No. 566,679 issued Aug. 25, 1896 toM. Gledhill; U.S. Pat. No. 1,544,469 issued June 30, 1925 to I. Malavalet al.; U.S. Pat. No. 1,771,505 issued Aug. 12, 1930 to GM. Wells etal.; and U.S. Pat. No. 3,550,502 issued Dec. 29, 1970 to G.H. Keith.Partial length liners, for example, are shown in U.S. Pat. No. 1,784,325issued Dec. 9, 1930 to K. Witzell and U.S. Pat. No. 2,775,164 issuedDec. 25, 1956 to F. G. Tillander et a1.

SUMMARY OF THE INVENTION It is an object of this invention to provide agun barrel system having a readily replacable liner, and which isespecially adapted for use with a revolving battery gun firing caselessammunition and utilizing separable chambers such as is shown in U.S.Pat. Application Ser. No. 18,099 filed Mar. 10, 1970 by E. Ashley, etal., to which reference may be made for a disclosure of a total gunsystem.

It is a particular object of this invention to provide a gun barrelsystem wherein any liner may be mated readily with any barrel withaccurate alignment of the rifling of their bores, and which alignmentwill not shift in use; and which liner may be removed readily from suchbarrel without damage to either the barrel or the liner, as forreplacement; and which system may be economically and readily fabricatedof notch sensitive refractor material.

A feature of this invention is a gun barrel system comprising a barrelforward section, a barrel aft section, means retaining said forward andaft sections together, a liner disposed within said aft section, meanslongitudinally capturing said liner between said forward and aftsections, means rotationally aligning said liner with said forwardsection, and means for facilitating ready and nondestructive removal ofsaid liner from said aft section.

BRIEF DESCRIPTION OF THE DRAWING These and other objects, features andadvantages will be apparent from the following specification thereof sotaken in conjunction with the accompanying drawing in which:

FIG. 1 is a longitudinal cross-section of a barrel system according tothis invention; and

FIG. 2 is an exploded perspective view of the system of FIG. 1.

DESCRIPTION OF THE INVENTION The barrel system includes a forwardsection 20, an aft section 12, a liner 14, a collar 16, and a breechinsert 18.

The forward two, 20 is substantially a cylinder of a first outerdiameter having a bore 20 therethrough, an aft enlargement 22 having asecond, larger outer diameter providing an outer, forward shoulder 24,an aft counterbore enlargement 26, two, longitudinally extending,diametrically spaced apart cups 28 into the side wall, and two,longitudinally extending, exterior, diametrically spaced apart flats 29.The enlargement has an inner transverse face 30 and an outer transverseface 32. The inner bore 20 is rifled, at 33, the rifling being orientedwith respect to the cups 28. A recess 86 is provided to cooperate with amulti-barrel clamp, not shown.

The aft section 12 is substantially a cylinder of a third outer diameterequal to said second outer diameter, having a bore 34 thereon equal indiameter to the bore enlargement 26, and partially occluded at its aftend by an integral annular ring 36 providing a transverse annular faceor shoulder 38, and having an inner diameter at 40 which is larger thanthe diameter of the bore 20. The forward outer end has two diametricallyspaced apart projections 41 extending longitudinally forward from thefront face 42 and is threaded at 43; and the aft outer end includes aplurality of interrupted threads 44.

The collar 16 is substantially a cylinder having a first inner diameter46, and a larger second inner diameter 48, providing a transverseannular face of shoulder 50. The aft end of the bore is threaded at 52.A plurality of wrench receiving radial blind bores 54, and threadedradial bores 56 with set screws 58 are also provided.

The liner is substantially a cylinder having an outer diameter 64 equalto the diameter of the bore 34 and an inner diameter 66 equal to thediameter of the bore 20, and an aft face 67. The two diametricallyspaced apart projections 68 of the thickness of the liner wall extendlongitudinally forward from the front face. The liner is rifled, at 69,the rifling being oriented with respect to the projections 68.

The breech insert 18 is substantially a cylinder having an outerdiameter 70, an inner diameter 72 larger than the inner diameter 66 byat least the rifling depth, an annular reduced diameter 74 equal to thediameter 40 providing a transverse face 76, an aft conical enlargement78, and a plurality of threaded bores 80, aligned with respectivethreaded bores 82 in the aft section 12, receiving screws 84.

The barrel assembly is readily assembled with the liner 14 being thrustrearwardly into the aft section 12 until it bottoms on the transverseface or shoulder 38. The forward end of the liner is inserted into thecounterbore 26 of the forward section 10 with the projections 68 matingwith the cups 28 and the projections 41 mating with the flats 29. Thecollar 16 is slid aft onto the forward section 10 and threaded onto theaft section 12 to capture the liner. The breech insert 18 is thrustforward into the aft section and locked against rotation by the screws84.

The barrel assembly is readily disassembled with the collar 16 beingthreaded off the aft section to release the aft section with the linertherein. The breech insert is removed, exposing the liner aft face 67.1f the liner is siezed in the aft section it may be pressed out byapplying longitudinal pressure to the exposed aft face 67 whilerestraining the aft section.

The mating projections 68 and cups 28 accurately align the respectiverifling of the liner and the forward section, and preclude torsionalshifting at the interface of the liner and forward section whilepermitting torsional shifting of the aft end of the liner.

The mating projections 41 and flats 29 accurately align the aft sectionwith the forward section, to align the aft locking lugs 44 with theforward clamping recess 86.

The counter-bore 26 receiving and overlapping the forward end of theliner serves two functions. it provides ready and fixed axial alignmentbetween the forward section bore 20 and the liner bore 65. It alsoprovides a two state gas seal. As the bullet passes over the overlap itcentrifugally presses the liner against the forward section, andafterwards the convolutions provide a static labyrinth seal.

The shoulders 30 and 38 longitudinally capture the liner with 360'engagement and preclude rearward movement of the aft face of the liner.lf desired, to provide a refractory transverse face at the immediate aftend of the barrel assembly, the breech insert may be omitted, and areduced annulus of the liner, having an outer diameter equal to thediameter 40, may be extended to be flush with the aft face of the aftsection.

Locating the interface of the forward and aft sections adjacent theforward end of the liner serves two functions. lt permits readymachining of the cups 28 which are thereby immediately adjacent the endof the section. Together with the exposable aft annulus of the liner, itpermits the non-destructive forwardly removal, by pushing, of the linerfrom the aft section. it is not necessary to screw or hook into theliner to pull it out.

it will be appreciated, that if desired, the projection 41 may beprovided on the forward section and the flats on the aft section 12.Similarly, although the machining will be slightly more complex, theprojections 68 may be provided on the forward section, within thecounterbore, and the cups 28 may be provided in the liner. This willenhance the fracture resistance to notching of the liner.

While there has been shown and described a preferred embodiment of thisinvention, it will be appreciated that the invention may be embodiedotherwise than as herein specifically illustrated or described, and thatcertain changes in the form and arrangement of parts and in the specificmanner of practicing the invention may be made without departing fromthe underlying idea or principles of this invention within the scope ofthe appended claims.

We claim:

1. A gun barrel system comprising:

a forward barrel section having a forward end and an aft end;

an aft barrel section having a forward end and an aft end;

first means removably securing said forward barrel section to said aftbarrel section, with said aft end of said forward barrel sectionadjacent said forward end of said aft barrel section;

a liner removably disposed at least in part in said aft barrel sectionand having a forward end and an aft end;

second means, for longitudinally aligning said liner in said aft barrelsection, including a first portion on said aft end of said forwardbarrel section and a second portion on said aft barrel section;

said liner, at its said aft end, having an aft transverse face, whichaft face has an outer annular portion and an inner annular portion, andat its said forward end, having a forward transverse face;

said aft barrel section entirely transversely clearing said forwardtransverse face of said liner; and

said second portion of said second means abuting said outer annularportion of said aft transverse face of said liner and thereby limitingaftward movement of said liner with respect to said aft barrel section,and clearing said inner annular portion of said aft transverse face ofsaid liner.

2. A system according to claim 1 further including:

a breech insert removably secured to said aft end of said aft barrelsection and overlying said inner annular portion of said aft transverseface of said liner.

3. A system according to claim 2 wherein:

said inner annular portion of said aft transverse face of said liner islongitudinally substantially coextensive with said aft end of said aftbarrel section.

4. A gun barrel system comprising:

a forward barrel section having a forward end and an aft end;

an aft barrel section having a forward end and an aft end;

first means rotationally aligning and removably securing said forwardbarrel section to said aft barrel section, with said aft end of saidforward barrel section adjacent to and longitudinally overlapping withsaid forward end of said aft barrel section; a liner disposed at leastin part in said aft barrel sec' tion and having a forward end and aftend; and second means, for longitudinally aligning said liner in saidaft barrel section, including a first portion on said aft end of saidforward barrel section and a second portion on said aft barrel section.

5. A system according to claim 4 wherein:

said aft end of said forward barrel section and said forward end of saidliner mutually longitudinally overlap.

6. A system according to claim 5 wherein:

said first means includes a least a projection extending longitudinallyfrom one of the group consisting of said aft end of said forward barrelsection and said forward end of said aft barrel section, and a matinglongitudinally extending recess in the other of said group.

'7. A system according to claim 4 wherein:

said forward end of said liner has a forward transverse face; and

said second means includes a counter-bore extending longitudinally intosaid aft end of said forward barrel section, a recess extendinglongitudinally further into said aft end of said forward barrel sectionfrom said counter-bore, and a projection for mating with said recess andextending longitudinally from said forward transverse face of saidforward end of said liner.

# i i i i

1. A gun barrel system comprising: a forward barrel section having aforward end and an aft end; an aft barrel section having a forward endand an aft end; first means removably securing said forward barrelsection to said aft barrel section, with said aft end of said forwardbarrel section adjacent said forward end of said aft barrel section; aliner removably disposed at least in part in said aft barrel section andhaving a forward end and an aft end; second means, for longitudinallyaligning said liner in said aft barrel section, including a firstportion on said aft end of said forward barrel section and a secondportion on said aft barrel section; said liner, at its said aft end,having an aft transverse face, which aft face has an outer annularportion and an inner annular portion, and at its said forward end,having a forward transverse face; said aft barrel section entirelytransversely clearing said forward transverse face of said liner; andsaid second portion of said second means abuting said outer annularportion of said aft transverse face of said liner and thereby limitingaftward movement of said liner with respect to said aft barrel section,and clearing said inner annular portion of said aft transverse face ofsaid liner.
 2. A system according to claim 1 further including: a breechinsert removably secured to said aft end of said aft barrel section andoverlying said inner annular portion of said aft transverse face of saidliner.
 3. A system according to claim 2 wherein: said inner annularportion of said aft transverse face of said liner is longitudinallysubstantially coextensive with said aft end of said aft barrel section.4. A gun barrel system comprising: a forward barrel section having aforward end and an aft end; an aft barrel section having a forward endand an aft end; first means rotationally aligning and removably securingsaid forward barrel section to said aft barrel section, with said aftend of said forward barrel section aDjacent to and longitudinallyoverlapping with said forward end of said aft barrel section; a linerdisposed at least in part in said aft barrel section and having aforward end and aft end; and second means, for longitudinally aligningsaid liner in said aft barrel section, including a first portion on saidaft end of said forward barrel section and a second portion on said aftbarrel section.
 5. A system according to claim 4 wherein: said aft endof said forward barrel section and said forward end of said linermutually longitudinally overlap.
 6. A system according to claim 5wherein: said first means includes a least a projection extendinglongitudinally from one of the group consisting of said aft end of saidforward barrel section and said forward end of said aft barrel section,and a mating longitudinally extending recess in the other of said group.7. A system according to claim 4 wherein: said forward end of said linerhas a forward transverse face; and said second means includes acounter-bore extending longitudinally into said aft end of said forwardbarrel section, a recess extending longitudinally further into said aftend of said forward barrel section from said counter-bore, and aprojection for mating with said recess and extending longitudinally fromsaid forward transverse face of said forward end of said liner.